The late Irving “Bud” Fried (1920–2005) blazed a trail through high-end audio’s formative years, first as an importer of classic British gear and later, starting in the 1970s, as a manufacturer of transmission line (TL) speakers under the Fried name. His strongly held beliefs about loudspeaker design were based, as he put it, upon the inexorable laws of physics, and he wasn’t afraid to promote and defend his ideas within the audiophile community. Fried maintained that the ideal loudspeaker would preserve the audio signal’s time coherency, which explains his fondness for the non-resonant bass response of TL designs. However, his pet preference for series, rather than parallel crossover networks, seems a bit quaint today after 40 years of progress in this field.
Fried Products Corporation, owner of the Fried and IMF brands, approached Salk Sound during 2012 with the idea of designing and marketing a TL speaker under the Fried name. This seemed like a natural fit as Salk Sound was already manufacturing TL speakers, and Jim Salk, founder of Salk Sound, decided to take up the challenge. Suffice it to say that the Fried/IMF brand names are now licensed exclusively to Salk Sound. The first speaker in the new line, says Jim Salk, “is very similar to our SongTowers. It plays deeper since it has 7″ woofers, and we used a series crossover rather than a parallel one. Other than that, both speakers are based on roughly the same concept.”
Jim Salk described for me the Fried Tower’s design considerations: “A team of people were involved in this first Fried project. I knew Bud used Hiquphon tweeters in the past and chose a tweeter model that was originally developed by Oskar [Wrønding] for him. I next looked for a moderately priced woofer with good performance characteristics. The Peerless model we chose was very reasonably priced, but used a lot of copper in all the right places. It was an excellent performer for the money. I asked Paul Kittinger to come up with a transmission-line cabinet for this model. Paul has done quite a few TL cabinet designs for us and looked at various TL formats. My initial request was that he develop a standard folded TL design. While this modeled fairly well, he also looked at a mass-loaded quarter-wave design similar to that used in our SongTowers. As happens on occasion, the mass-loaded design modeled in a slightly superior fashion. So we had a quandary. Do we assume Bud would have opted for the slightly superior enclosure or do we stick with the type of TL cabinet he was best known for? In the end, while it was not necessarily the approach Bud would have taken (tools to model these designs were not available in his day), we opted for the slightly superior mass-loaded design.”
“Once we had a cabinet design, we turned the project over to Dennis Murphy for crossover design. Dennis developed a standard parallel crossover for the speaker, which optimized the capabilities of the drivers. Once we had optimized this design, he took on the task of converting the design to a series crossover more in keeping with what Bud would have done. The resulting slopes were steeper than with Bud’s ideal loudspeaker design, but certainly consistent with some of the crossover designs he offered (we were supplied with all previous lab notes and crossover schematics). In looking over Bud’s lab notes, he had quite a few strongly held theories, but his designs did not always conform to his definition of the perfect loudspeaker (based on his white papers). These speakers obviously take some liberties with Bud’s ‘ideal’ design philosophies as well.”
The Tower’s cabinet is definitely not a classic TL in the tradition of A.R. Bailey’s folded line or Robert Fris’ DALINE (Decoupled Anti-Resonance Line), whereby the rear chamber housing the woofer is vented into a folded line. I’m certain that Bud Fried would have had difficulty in correctly identifying the Tower’s as a TL. And that’s because a mass-loaded transmission line (ML-TL) is a hybrid design in which an acoustically damped line is terminated through a bass-reflex-style vent. No wonder this design is often identified as just a tall bass reflex with no independent significance. But that clearly isn’t the case, as Martin King, who popularized this design, has shown. I used Armin Jost’s excellent AJHorn software to model two versions of the Tower cabinet. The first, as a normal bass reflex, and the second with the internal volume stretched out as a one-meter-long quarter-wave resonator. In both cases, the net interior volume was assumed to be two cubic feet and the box tuning frequency was set to 30Hz. The simulation results were similar, but did highlight two advantages of the ML-TL model. Damping in the deep bass was improved relative to that of a standard bass-reflex box, and the line appeared to distribute the port output more evenly in the bass region, as upper-bass energy (70 to 200Hz) was shifted to the midbass to give a smoother overall response.
Dacron stuffing, taking up about half of the line’s interior volume, is used to preferentially attenuate standing waves higher in frequency than the quarter-wave fundamental. Jim Salk relates that as far as he’s been able to determine, Bud Fried preferred wool, but that listening tests did not find significant audible differences between wool and Dacron. The speaker ships with a spiked footer assembly that attaches to the bottom of the cabinet and provides a firm footing on carpeting. The effective acoustic crossover slopes are fourth order at 2.8kHz and are achieved by using series second-order electrical networks. The drivers are arranged in a D’Appolitto MTM configuration for improved vertical dispersion. Driver integration is quite good, especially considering the task at hand of mating 7″ woofers to a 3⁄4″ tweeter. The midrange is slightly emphasized relative to the upper mids, which serves female voice well. Although the tweeter can soak up fair amounts of power, and is capable of excellent speed and treble finesse, some compression was evident during the scaling of loud passages. Bass extension measured flat to 40Hz, though, at least in my room, the bass balance was slightly uneven, with emphasis centered on the midbass band at the expense of the upper bass. In general, resolution of bass lines was excellent, with tight control and ample rhythmic finesse. In bass punch, the Fried Tower easily eclipsed the headroom of the SongTower.
Fried Tower’s measured impedance minima are 4 ohms at 200Hz and 2.7 ohms at 2.7kHz, the latter minimum being crossover related. That leaves the door wide open for power-amplifier/source-impedance interactions at these impedance minima. For example, switching from a solid-sate power amp with a source impedance under 0.1 ohms to a tube amp with a source impedance of 1.6 ohms resulted in about a 1dB reduction in SPL near these minima. The audible result was a lean upper-bass range and an upper-midrange dip that shifted soprano and violin tonality toward a darker and coarser timbre than the real thing.
What you ultimately think of this speaker will be a strong function of the partnering power amp, the safest bet being an amp with a high damping factor. When I asked Jim Salk for amp recommendations he mentioned an inexpensive option such as the Emotiva XPA-2, several of Frank Van Alstine’s designs, and the BAT VK600. To that list I can safely add the expensive Lamm Audio M1.2 Reference monoblocks and the affordable PrimaLuna Dialogue Premium integrated amp operated in triode mode with a pair of KT120. Even with an optimal power-amp choice, the Tower is positively not a “flame thrower,” meaning a bright-sounding speaker capable of scorching one’s eyebrows. Its presentation tends to be concert-hall-like with the treble taking a bit of a backseat to the midrange.
My preferred toe-in angle was with the tweeter pointing toward the listening seat—otherwise the integration between the drivers suffered in the upper midrange. Image outlines were tightly focused and easy to pinpoint within the confines of a transparent and nicely layered soundstage. The Peerless Nomex cone woofers acquitted themselves extremely well. I was surprised by this woofer’s level of midrange clarity and ability to reproduce clean and pure harmonic textures. Resolving low-level detail in a multitrack mix was child’s play—no strain involved in picking out pan-pot effects and vocal overdubs. Spec-wise this woofer may not look particularly impressive, but it delivered the sonic goodies. Toward the end of the review period, I coupled the Fried Tower with my upgraded Leak Stereo 20 amplifier that had been modified by Stu Remington to operate in pentode mode. Within the Leak’s power limitations of about 12Wpc, this combo turned out to be a match made in heaven resulting in exquisitely sweet midrange textures and a clear and precise top end.
As Jim Salk says, “The process of trying to build on a legend is both interesting and challenging. As we continue our work, our goal is to eventually get as close to Bud’s definition of the ideal loudspeaker as possible.” The Bud Fried Tower undoubtedly does justice to his legacy and does so at an affordable price point that should attract music lovers and audiophiles alike. The Bud Fried Tower not only earns a no-brainer thumbs-up recommendation at its price point, but I find it to be competitive with any box speaker I’ve evaluated under $6k. I’ve enjoyed its company over a lengthy review period and would advise you give it a serious audition.
SPECS & PRICING
Frequency response: 35Hz–20KHz (+/-3dB)
Sensitivity: 88dB 2.83V/1m
Nominal impedance: 4 ohms
Minimum recommended amplification: 35Wpc tube/50Wpc solid-state
Weight: 58 lbs. each
Dimensions: 8.5″ x 45″ x 14″
40 West Howard St, Suite 204
Pontiac, MI 48342
Lamm Audio M1.2 Reference monoblocks, PrimaLuna Dialogue Premium Integrated amp, PAOLI 60M monoblocks with Curcio upgrade, Leak Stereo 20 with Stu Remington upgrade; EAR DAC, Sony XA-5400 SACD player with ModWright Truth modification; Kuzma Reference turntable; Kuzma Stogi Reference 313 VTA tonearm; Clearaudio Da Vinci V2 MC phono cartridge; Pass Labs XP-25 phono stage; Pass Labs XP-30 line preamplifier; FMS Nexus-2, Wire World, and Kimber KCAG interconnects; Acoustic Zen Hologram speaker cable; Sound Application power line conditioners
By Dick Olsher
Although educated as a nuclear engineer at the University of Florida, I spent most of my career, 30 years to be exact, employed as a radiation physicist at the Los Alamos National Laboratory, from which I retired in 2008.More articles from this editor